1. American Community Survey:
What it is and How it’s Used
Elizabeth Lukanen, Senior Research Fellow
Joanna Turner, Senior Research Fellow
State Health Access Data Assistance Center (SHADAC)
University of Minnesota
March 7, 2013
HCFO Webinar
Funded by the Robert Wood Johnson Foundation and Federal and State Agencies
2. Outline
• Federal surveys to monitor health insurance
coverage and access
• Introduction to the ACS
– Methodology
– Type of data collected
– Data products and release schedules
• Obtaining the data
– Public Use Microdata Sample (PUMS) files
– Integrated Public Use Microdata Series (IPUMS)
– Tables of pre-tabulated estimates (multiple sources)
2
4. Research Needs for Monitoring Health
Insurance Coverage
• Consistent estimates
• Trends over time
– Monitor impacts of health reform
• Comparisons across states
• Subpopulation analysis
– Race/ethnicity, poverty, age
– Counties/sub-state areas
• Access to microdata
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5. Key Federal Survey Data Sources
• General household survey
– ACS: American Community Survey
• Employment/Income survey
– CPS: Current Population Survey
• Health surveys
– NHIS: National Health Interview Survey
– MEPS-HC: Medical Expenditure Panel Survey-
Household Component
– BRFSS: Behavioral Risk Factor Surveillance System
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6. Current Population Survey (CPS)
Good
• Historic trends
• State-level estimates
• Several control
variables available Bad
• State-specific public • Low sample in
health insurance smaller states
program names • 10% of respondents
• Timely data release have entire Ugly
supplement imputed
• Concerns about the
coverage questions
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7. American Community
Survey (ACS)
• SAMPLE SIZE!
• Sub-state estimates
• Robust subpopulation
analysis
The ACS Sample
• Representativeness is almost
15 TIMES LARGER
• Current health than the
CPS Sample
insurance coverage
measured
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8. Feasibility of State-Level Health Insurance
Estimates from Federal Surveys
ACS SIPP CPS NHIS MEPS BRFSS
HC
State-level estimates possible?
All states *
Some states ~20 ~20 ~35
State identifiers available on
public use files?
Sample size by state
High 353K 9K 20K 13K 5K 20K
Median 44K 1K 3K 1K 400 7K
Low 6K 160 2K 110 <100 2K
* Two-year averages recommended.
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9. Availability of Health Outcome Measures
in Federal Surveys
ACS CPS SIPP NHIS MEPS BRFSS
HC
Health insurance coverage
Point in time
Prior calendar year
Affordability of coverage/
comprehensiveness of coverage
Access to care/barriers to care
Health care use
Affordability of care
Quality of care
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11. American Community Survey (ACS)
• General household survey conducted by the U.S.
Census Bureau
– Mandatory survey
• Replacement for the “long form” of the decennial census
– Collects detailed economic, social, demographic, and housing
information annually instead of once every ten years
– Provides communities with up-to-date information on key
demographics and policy relevant data
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12. Decennial Census
now limited to 10
questions
• # of people
• Home
owned/rented
• Sex
• Age
• Race and
Hispanic origin
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13. Methodology
• Data collected continuously with monthly
samples
• Collects sample in all counties or county
equivalents in the U.S. every year
• About 3.5 million addresses sampled each year,
collecting responses from over 2 million
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14. Methodology (2)
• Surveys the entire population including:
– Housing units
– Institutional group quarters
• For example nursing homes & prisons
– Non-institutional group quarters
• For example college dorms & military barracks
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15. Methodology (3)
• 4 modes of data collection:
– Mail
– Internet option added in 2013
– Phone for non-response follow-up
– In-person sub-sample for non-response follow-up
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16. Data Collected
• Age, sex, race, Hispanic origin
• Housing
• Ancestry, citizenship, language spoken at home
• Education, occupation, travel to work
• Marital status, fertility
• Income, poverty, food stamp participation
• Disability, health insurance coverage
• Veteran status
For a complete list of topics click here
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18. Data Products
• 1-year estimates (12 months)
• Multiple years pooled together to produce
reliable estimates for areas and subgroups
with smaller population
– 3-year estimates (36 months)
– 5-year estimates (60 months)
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19. Years Available
• Testing began in 1999
• Fully operational in 2005
• Group quarters added in 2006
• Health insurance coverage added in 2008
– First 5-year file (2008-2012) with health
insurance coverage will be available in winter
2013
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20. Annual Release Schedule
• 1-year estimates released in September
– For example 2011 estimates were released
September 2012
• 3-year estimates released in October
• 5-year estimates released in December
• The public use files are released about 1-2
months after the pre-tabulated estimates
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21. Annual Release Webinar
• SHADAC hosts an annual data release
webinar with Census Bureau experts in
September
– Discuss new ACS and CPS health insurance
coverage estimates and any changes to the
survey questions or methodology
For an archive of past webinars click here
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23. Obtaining the Data
• Data access point will have implications
for analytic options
• Three common ways to get data
1. Public Use Microdata Sample (PUMS) files
2. Census Bureau pre-tabulated estimates
(from full sample)
3. Other pre-tabulated estimates (from PUMS)
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24. Public Use Microdata Sample (PUMS) Files
• Subset of full file (1-year file is about 1% of the
U.S. population)
• Smallest geography available is the Public Use
Microdata Area (PUMA) for 1-, 3- and 5- year
files
• Contains about 100,000 people and nest within states
• Counties with larger populations are subdivided into
multiple PUMAs
• In more rural areas PUMAs are made up of groups of
adjacent counties
• PUMAs can be made up parts of several different
counties
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27. Accessing PUMS Files
• Download through Census Bureau
– Available as CSV or SAS files
– Need statistical software
• Access through DataFerrett
– A menu-driven system; no statistical software needed
– Free, but need to register and download tool
• Download through the University of Minnesota’s
Integrated Public Use Microdata Series (IPUMS)
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29. IPUMS
• Take the PUMS files from the Census
Bureau and harmonize variable names,
coding schemes, and documentation
– Great for studying changes over time
• Create a consistent set of constructed
variables on family interrelationships
– Easier analysis of family structures and
characteristics
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30. IPUMS (2)
• Easy to use and free
• Download only what you need
– SPSS, SAS, STATA
• Contains SHADACs added policy relevant
variables
– Health Insurance Unit (HIU)
– Federal Poverty Guidelines (FPG)
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32. Pre-tabulated Estimates from Census
Bureau’s American FactFinder (AFF)
Health Insurance Coverage: 2011
Source: 2011 American Community Survey downloaded from AFF at
http://factfinder2.census.gov
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33. Geography Available through AFF
1-year 3-year 5-year
Published Geography Population > Population > All areas
65,000 20,000
Nation, States, & DC All All All
Congressional Districts All All All
Counties About 25% About 59% All
School Districts About 7% About 24% All
Metro & Micro Statistical About 54% About 97% All
Areas
Zip Codes None None All
Census Tracts None None All
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35. Robert Wood Johnson Foundation
(RWJF) Data Hub
Percent Uninsured, 2011
http://www.rwjf.org/en/resear
ch-publications/research-
features/rwjf-datahub.html
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36. Choosing an Access Point
Example PUMS IPUMS AFF
Analytic Need Microdata
Define children 0 to 18
Lowest SE possible
Detailed family relationship
County, Census tract, zip
code
“Universe” e.g. limiting to
the non-institutionalized
population
Health Insurance Unit (HIU)
Customized income range
(e.g. FPG vs FPL)
No access to statistical
software
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38. Example Questions
• How will the impacts of the ACA differ by state?
• Will a states’ approach to implementation impact
the effect of the ACA on coverage?
• How many uninsured are in a state and where
do they live? What is their demographic profile?
• How many kids in each county are eligible for
CHIP or Medicaid but not enrolled?
• How many people in my state will be eligible for
Medicaid under ACA?
• How will the impacts of the ACA differ by race,
age, etc.?
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39. Possible Additional Question in 2014
• The Census Bureau is proposing the
addition of an exchange or premium
subsidy question in 2014
• This question would follow the current
health insurance coverage question
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40. SHADAC ACS Resources
• “Understanding 1-, 3-, and 5-year ACS”
– http://www.shadac.org/publications/understanding-1-3-and-5-year-acs-
estimates-summary-tabulations-and-public-use-files
• “Defining Family for Studies of Health Insurance Coverage”
– http://www.shadac.org/publications/defining-family-studies-health-
insurance-coverage
• “Monitoring the Impacts of Health Reform at the State Level: Using
Federal Survey Data”
– http://www.shadac.org/publications/monitoring-impacts-health-reform-
state-level-using-federal-survey-data
• “Number of Children with Health Coverage Increases During
Economic Downturn”
– http://www.shadac.org/publications/keeping-kids-covered-number-
children-health-coverage-increases-during-economic-downturn
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41. Elizabeth Lukanen and
Joanna Turner
Senior Research Fellows
State Health Access Data Assistance Center
University of Minnesota, Minneapolis, MN
612-624-4802
elukanen@umn.edu and turn0053@umn.edu
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